Field
This non-provisional U.S. patent application relates generally to mechanical torque and power measurement and more specifically to a systems and methods for measuring drivetrain power transmission.
Description of Related Art
Bicycles are a popular type of transportation device. A bicycle is generally constructed to include a pair of wheels, a frame, a seat, handlebars, a steering mechanism, and a drivetrain. The drivetrain generally includes a crank assembly, a power transfer element, and a transmission element that allows a cyclist to adjust a drivetrain ratio (gear ratio). The crank assembly typically includes two pedals used by a cyclist to couple rotational power to the drivetrain.
While riding a bicycle, a cyclist typically transmits rotational power to the bicycle through the crank assembly. In certain training scenarios, quantifying the rotational power is useful for tracking and improving cyclist performance. In other scenarios, quantifying rotational power is useful for controlling power output of motorized rider assist systems. For example, a motorized rider assist system can include a battery, an electric motor that is coupled to the drivetrain, and a controller that adjusts power to the electric motor in proportion to rotational power provided by the cyclist.
Certain conventional techniques perform a direct strain or load measurement on drivetrain elements that move relative to the bicycle frame. Such techniques require signal transmission between moving drivetrain elements and the bicycle frame, thereby reducing overall reliability while increasing cost and system complexity. Other conventional techniques fail to accurately measure power transmitted from the cyclist to the drivetrain, limiting usefulness in certain applications. Thus, there is a need for addressing these issues and/or other issues associated with the prior art.